For a few minutes she held the attention of the United Nations security council. Today, she is once more a frightened 18-year-old Nepalese peasant living under the threat of violence from Maoist guerrillas.

When Sita Tamang spoke at the UN in New York last month about her experiences as a child soldier, her testimony moved even the most hardened of diplomats. Flanked by Radhika Coomaraswamy, the UN special representative for children and armed conflict, the school student described how her two years with the Maoists had been "sad and painful".

But though she spoke in New York under a false name, Manju Gurung, Tamang was identified from photographs. Last Sunday, a group of Maoists arrived at her village in the central Chitwan district to issue a clear threat. Tamang was out tending goats in woods nearby and was summoned to meet them.

"They told me that my intentions were not good ... and told [me] and my mother that anything can happen to me in the future," Tamang told a Nepalese news magazine this week. "Of the five, I recognised the woman. I don't remember her name but I had first met her four years ago."

The Maoist rebels signed a peace agreement in 2006, ending a 10-year conflict that had left an estimated 13,000 people dead. Thousands of young people ended up as guerrillas as the insurgents imposed forced conscription of one child per household. Others joined voluntarily to fight against a corrupt, incompetent administration and discrimination.

Tamang had described to the UN how she had been forced to join the Maoist army in September 2005, at the age of 13. Initially told she could return home after a week, she received weapons training and ended up spending two years with the rebels.

"Many of my friends had died fighting and many had become disabled while fighting. Most of us were weak. During the war, at times, we wouldn't be able to eat for an entire week. Sometimes, we would survive on water and cornflour," she said. Tamang also described long days of digging ditches.

Since the end of hostilities, Maoist fighters have been confined to UN-monitored camps, while the Maoist leaders have joined mainstream politics with their party winning the most seats in 2008 elections.

However, frustrations are growing at the continued failure to reach a constitutional deal to give the Maoists a role in government and to integrate nearly 20,000 former combatants into the national armed forces.

Last month, the Maoists called a general strike that shut down Nepal, one of the poorest countries in the region, for more than a week. Street demonstrations turned violent with clashes between communist supporters and police. A new deadline for a deal on the composition of the government passed yesterday.

Tamang said she had been given a command position but had then been demoted to a cook after being accused of faking sickness to avoid work. She also described how she had been stigmatised on returning home and returned to the Maoists after just 10 days in her village. She went home permanently in May 2007.

A Maoist commander admitted that a group of former rebels had been sent to see Tamang, according to a journalist based in Chitwan.

The UN in Kathmandu said the organisation was "aware of concerns about Tamang's security" and that a team had been sent to assess the situation.

"Currently, Sita is continuing her school and living with her family. The UN and other human rights organisations are closely monitoring to ensure she is able to continue her normal life," a spokesman said.